There's a lot of content here with 27 different makers all pitching in to contribute stages. Overall, the vast majority of the stages range from OK to exceptional, some out of place, and one that was truly frustrating.

There's a lot of spotlight, spooky music, (too many breakfast memes), and enough Mario ghosts to last a lifetime. Considering that all of the stages were made independent of each other, it's not too surprising that a lot of stage share these concepts when it comes to spooky stuff. It's because of this that the morning after after playing, I have a hard time remembering a lot of stages. They weren't really bad or anything, but some of them weren't as memorable as others.

I wanted to wait till the morning after to see what stages still stick out as memorable to me. Looking back this morning some of the stages that still stick out to me include:

Kady's stages with the maze chase, newcomer Dribix who made probably the best overall stage beating out a lot of veteran makers, the CosmicSense light-hearted avoidance, Lss who probably had the best visual presentation, Klazen's factory, and SpicyFishesKiller jump refresher puzzle gimmick.

Some of the stages along the way have some small boss fights, but the end of the game seemed very weird to me. After you beat all the stages you are presented with a boss encounter, which by it's design seems to have an air of finality to it the culminates with the classic dramatic avoidance.

But instead of the game ending, it keeps going into a series of more fights that seem completely random and disjointed from one another. Then there is some weird jump refresher platforming segment that leads into a random rock boss thing, which really wasn't that good especially compared to the what's before and after it. Then it just keeps going as more bosses of random guys come at you, and ultimately another dramatic final avoidance that is pretty stunning.

These fights by themselves are not bad, but stacking them right in a row at the end of the game feels like they were tacked on without sense of game flow. It feels like you are being being forced into a boss rush type situation which is exhausting as a player. I feel like the game would have been better served by placing these earlier in the game at certain intervals to break up the platforming instead of dumping them all on the player at the end.

There's a lot to see and do in this game and the production is great. There's a bunch of truly memorable stages, a bunch of decent ones, a lot of forgettable ones, and a few that felt like they didn't have much to do with the Halloween theme. Given the length of the game and the nature of the final bosses, even as good as the true finale is, you may find yourself glad that it's finally over.

Collabs are great, because many ideas come together, which a single person wouldnt be able to think of and offer a great variety when it come to gameplay and gimmicks.

Sadly, there were quite a few stages which seemed really uninspired. Pretty much just needle with a few Halloween-themed visuals.

Because many people work together and make their stages seperatly, it's hard to balance everything and get a nice difficulty curve going. Some stages were out of balance and if I remember correctly, this game was meant to be around a 40~ish del-fruit difficulty. I think some stages were beyond that point.

Also the endgame felt completly out of place. You basically fight 4 bosses in a row, some were decent, some not. But alone the fact that you have such a long boss sequence to get through made me feel like playing a totally different game. But that could be just me. Also the difficulty was not a 40 for me at that point.

But still, the game is great and there a quite a few highlights like Dibixs stage for example. He manages to hide his needle behind a beautiful and well created Halloween-themed stage which hit the right difficulty I was expecting from this game. Also obsecure stages like HopPros stages made it a unique journey.

I definitly recommend that game, but I dont think it is well suited for complete beginners, which I hoped it would be.

Really long halloween collab. Fairly well-made, there's a lot of variety, with the stages being completely different from each other, both visually and gameplay-wise. Nice and calm death sound, particularly welcome at the needle sections, and the ghost kid sprite is cute.
The game consists on 27 linearly structured stages of varied lengths and themes, followed by a boss rush of sorts.

-128's stage is a nice way to start the game. It's a light-hearted stage consisting of needle and some moving obstacles, with some amazing Halloween visuals. The moving obstacles make the gameplay more eventful, while keeping the difficulty on the lower end, since they are easy to avoid. Also, the visuals are amazing.
-Kady's stage is a spooky maze of spider webs where your objective is to collect a couple keys to unlock the exit, while avoiding a creature you can't see. The music is unsettling, and I like how it gets more agitated as the creature approachs you. Once you reach the end of the stage, you'll find out that the creature chasing you is a lot less scary than you'd have expected. I don't love this stage like many people who played it do, but I certainly like it.
-Dlaston's stage is an alright trap stage. Some of the traps are a bit too precise for my liking, but it's fine. The falling pumpkin near the end of the stage (At the section with skeletons that throw bones at you) was quite unnecessary, too. It's the first area in the game to feature a boss, and it's a fairly fun boss, with a decent variety of attacks, all of which are fair.
-Kyir's stage is a jump refresher tower on the vein of his usual needle, but with an eerie tone. It's really fun, but almost criminally short.
-Darq's stage is another trap stage. It uses a "surprise needle" gimmick of sorts, where the jumps are formed as you get closer to them, along with some nicely timed flying spikes that always give you enough time to react and avoid them. I like it, although I see little to no Halloween atmosphere in it.
-Piece's stage starts out as straight needle, and later introduces some switches. It isn't anything impressive, but it's fun. It's also fairly long compared to the other stages so far. The boss looks bad, but gameplay-wise it's alright.
-Haegoe's stage is short, but displays a decent amount of variety. Features a flame that constantly chases you through needle, traps and a couple basic gimmicks, including a couple saves where you have to collect pumpkins in order to progress. Maybe it goes a little overboard with the flying obstacle traps at one of the saves? It's fun anyway.
-Raynius' stage is another super short stage. Features some ghosts that try to attack you with electricity, and a bit of needle. Doesn't have a lot to speak of, and it's too short to be anything at all. The boss is fun, though, and the way you defeat him is quite funny.
-RandomFangamer's stage is a short puzzle-ish section where you shoot switches to enable and disable platforms and spikes. Involves a couple traps, but there's only one per save at most, and the traps are funny anyway, so it's fine.
-Smartkin's stage is built around a gimmick where you have to collect all the candy at the screen in order to unlock the next one, while avoiding all sorts of obstacles. It's quite fun, and not too short or too long. The boss is nicely made, and has a decent variety of attacks.
-Cosmic's stage is an avoidance. I don't like it because most of it is simple pattern, and the RNG attacks are too fast, which makes it focus its difficulty on very specific spots of the fight. Still, it's not very difficult and probably won't block most people's progress.
-Zebbe's stage is a somewhat long (For this game's standards, anyway) platforming section filled with Super Mario ghosts. It's a mixed bag for me. I like the platforming itself, the needle sections are fun and controlling the chasing ghosts is neat, but I don't really like the way the stage is structured. The first part of the stage is filled with backtracking, and the second part branches into two paths, but the left path leads to a dead end, so it's only there to waste your time anyway. I also like how I pinpointed a glitch on this stage when I was testplaying it, but the glitch is still here on the final version (It's an odd skip which involves reaching the second screen, then trying to go back to the first screen to skip a decent amount of platforming). I don't take away points for glitches that don't affect the gameplay, but it's really odd to see that this still exists.
-Spicy's stage is a neat puzzle section involving a gimmick that allows the Kid to mark a specific location, then teleport to that location. It's interesting, and really well implemented, although, just like with Darq's stage, I don't see a lot of halloween in it.
-Dribix's stage is easily one of my favorites. Consisting of a mini-game setup where you have to find and visit houses to collect candy, it features super fun platforming involving basic needle, a couple moving spikes and lots of switches that unlock paths and flip the screen in various ways. It's fairly eventful, and while doesn't show any innovative gimmick, it certainly does a great job on making the old ones much more appealing. Due to its objective, it's also one of the most halloween-y stages in the game. At the end, there's also a boss. The witch that supposedly was helping you out of good will actually just wanted to steal your candy for herself, which she does once your bag is full. The boss is fairly fun, with a nice variety of attacks, and the ending of the fight is a funny touch. It's also the only boss in the game that actually has a clear reason to fight against you.
-Piranha's stage is basically a remake of I wanna Escape the Blackman, but a lot better. Your task is to collect 6 pages inside a house, then escape it. However, as you collect the pages, an eerie creature starts to chase you. This creature grows faster as you collect more pages, but fear not! You have a flashlight, and this flashlight scares the creature away if you focus the light on it, leaving you alone for a couple seconds. Your flashlight runs out of battery fairly quickly, so you have to be constantly collecting batteries as well. The creature gets faster as you collect more pages. You also have a map to aid you with finding the pages (Although it's not very hard to find them without the map either), which you can access by pressing 'M'. The visuals are really good, and the atmosphere it builds with the sound effects and visual effects is great. I liked Blackman's concept a lot, and I really loved to see it being well implemented in this game. Easily one of my favorite stages as well (Although I know that many people didn't like it).
-Erik's stage is way longer than any other stage in the game so far, being long enough to be a solid standalone fangame on its own. Consists mostly of needle with plenty of enemies you can shoot (And some that you can't shoot), but it also has its share of funny traps and minor gimmicks. It even has two bosses, the first one being really simple, but fun, and the second one being a bit more elaborate, and also fun. I liked this stage quite a bit overall. It's simplistic, but nicely made, and enjoyable all the way through.
-Wetwookie's stage is a needle stage with some moving obstacles. Features cute cats, shiny pumpkins and big kids with lanterns. Fun platforming, great visuals, one or two funny traps of sorts.
-Quentin's stage is mostly straight needle, although the last area introduces a gimmick involving killer water that moves up and down, forcing the player to look for safe spots. It's quite fun overall.
-Polaroid's stage is a reskinned Micromedley, but, as Whalington said, Micromedley is great anyway. It's a bunch of halloween-themed mini-games involving needle screens, killing enemies and other more specific tasks, and it's really fun. The boss is a lot harder than the previous bosses, though, and might be troublesome for unprepared players. It's divided into two phases, since the fight is fairly long and there's an avoidance in the middle of the fight. The main boss is The Lich from a couple stages ago, aided by a couple other foes. There's a lot of RNG, and The Lich's first phase consists of some really tricky attacks. Great stage overall, though the boss might a bit too hard.
-Patrick's stage involves a nice gimmick that allows you to break spikes. It's fun, and has a nice atmosphere. From the slimy creatures that mostly try to run away from you to the purple-haired girl, and the perfectly matching music, it's quite unsettling. I like it.
-Voider's stage is quite puzzle-ish, involving a fair share of different gimmicks that you have to combine in order to get through the different screens. There are two bosses and a section that almost could be considered a boss, but I guess they could be considered phases of the same boss if you want. The first one is nice, although simple, and the second one is quite well-made, making a nice use of one of the stage's gimmicks. There's not a lot of Halloween in this stage either, but it's creative, and I like it.
-Lonetree's stage uses a nice gimmick that allows you to walk in the air for a couple seconds. It's nice, although it requires some unnecessarely precise maneuver at some points. The last screen is also quite annoying until you get the hang of it, as you might end up activating the gimmick when you just want to double jump. It's a nice stage overall, although I didn't like some of its sections.
-Lss's stage is another of my favorites. Consisting of needle with various gimmicks involving shadows and light, it's easily the stage with the best atmosphere in the game. Each gimmick is announced by an angel statue beforehand in a riddle, which makes some of them easier to understand, while also making the stage a lot cooler. There's also a 'boss' at the end, and, unlike many other players, I loved it. It's not very difficult, and it forces you to keep moving in order to protect the three candles. It's probably the most creative boss in the entire game, and I like how you have to keep a balance between aggressiveness and carefulness in order to beat it. I loved it, just as much as I loved the rest of the stage.
-Jelly's stage is a combination of straight needle and basic gimmicks like vine jumps, double jump water and single jump water (An style of needle that is getting quite popular nowadays, and I'm definitely not complaining about it). It's solid, kinda of puzzle-ish, and pretty fun.
-Zapmunk's stage features a really interesting gimmick where jumping creates a legion of ghost kids to aid you, and if your Kid dies somehow, you'll become one of them (If all of your Kids die, you'll die, though). It's a really creative gimmick that makes needle jumps a lot easier, and thus this stage features a lot of tricky needle jumps, some of which are hard even with the aid of the legion of Kids. Really creative stage overall, though I'm not sure if it fits the halloween theme.
-Hop's stage is weird. It almost has what it takes to be unsettling, but the first few screens aren't anything special, and the actually interesting part consists of only two screens of platforming (One of which is needle and the other one being some sort of mini-boss), which is nowhere near enough to be remarkable at all. I like how the non-platforming screens build up to this section, but the section itself is just too short to be anything at all.
-Finally, Klazen's stage is a pretty well-made stage that alternates between creative puzzles and simple, straightforward platforming. Features a couple gimmicks, the most notorious one being the ability to possess artificial Kids' bodies and use them to activate all sorts of switches. It's fun, and I like pretty much everything about it.

Next up is the "??? stage", which is also known as the 'Boss Rush' section. It has five main boss sections (And a platforming section).
-The Heart is a pretty fun and well-made boss. It's difficult, has multiple phases, and they're all fair, but equally challenging. The music is pretty cool, too.
-The Hand Centipede is a weird avoidance that I honestly don't like that much. Visually, it doesn't look very good, and gameplay-wise it's not very fun either. The main reason for me to dislike it is the attack with the big eyes that spawn too close to the Kid to be properly avoidable, which ends up making it a lot more reliant on luck than it should. At least it's a short fight, which prevents this attack from being a major issue.
-Preceding the next boss, there's a short platforming section involving jump refreshers. It's a well-made puzzle-platforming section, but really, really short. Once you get past it, there's a big Thwomp, which is the next boss. It's a fun and simple fight, though maybe a bit too easy compared to everything else in the stage.
-The next boss section is a cluster of bosses. It's challenging, and I like how each boss behaves and attacks in a different way.
-Finally, the last boss section is an avoidance featuring the Dark Ghost Kid. It's really well-made, with some really good visual effects and it's really fun to play as well: Challenging from the beginning to the end, but always fair, with readable patterns and RNG attacks.
While I like the bosses individually, I have to agree with Paragus when he says that stacking one after another like a Boss Rush feels really exhausting, specially since the fights are linear, unlike in a normal fangame Boss Rush, where you can play them in any order you want. Still, I liked most of this stage a lot.

Overall, I loved this game as a whole (Some stages more than others). It's one of those fangames with so much variety it's almost impossible to not like at least a bit of it, although it's really hard to like everything about it exactly for the same reason. Really glad to have played it twice, and surprised that both playthroughs were so enjoyable. Highly recommended.